Detecting overlap

I have code now, thanks to IdleMind that allows me to drag a Picture Box around on a form.



I have another PictureBox on the form.


When I stop dragging the PictureBox...I want to be able to detect if the border of the one PictureBox  is overlapping the border of other PictureBox.




My current code should work with a new C# Windows App project, for that is what I am using to test these concepts with.




using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace WindowsApplication2
{
      /// <summary>
      /// Summary description for Form1.
      /// </summary>
      public class Form1 : System.Windows.Forms.Form
      {
            private System.Windows.Forms.PictureBox pictureBox1;
            private System.Windows.Forms.PictureBox pictureBox2;
            /// <summary>
            /// Required designer variable.
            /// </summary>
            private System.ComponentModel.Container components = null;

            private int startX, startY;

            public Form1()
            {
                  //
                  // Required for Windows Form Designer support
                  //
                  InitializeComponent();

                  //
                  // TODO: Add any constructor code after InitializeComponent call
                  //
            }

            /// <summary>
            /// Clean up any resources being used.
            /// </summary>
            protected override void Dispose( bool disposing )
            {
                  if( disposing )
                  {
                        if (components != null)
                        {
                              components.Dispose();
                        }
                  }
                  base.Dispose( disposing );
            }

            #region Windows Form Designer generated code
            /// <summary>
            /// Required method for Designer support - do not modify
            /// the contents of this method with the code editor.
            /// </summary>
            private void InitializeComponent()
            {
                  this.pictureBox1 = new System.Windows.Forms.PictureBox();
                  this.pictureBox2 = new System.Windows.Forms.PictureBox();
                  this.SuspendLayout();
                  //
                  // pictureBox1
                  //
                  this.pictureBox1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
                  this.pictureBox1.Location = new System.Drawing.Point(104, 80);
                  this.pictureBox1.Name = "pictureBox1";
                  this.pictureBox1.TabIndex = 0;
                  this.pictureBox1.TabStop = false;
                  //
                  // pictureBox2
                  //
                  this.pictureBox2.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
                  this.pictureBox2.Location = new System.Drawing.Point(328, 216);
                  this.pictureBox2.Name = "pictureBox2";
                  this.pictureBox2.TabIndex = 1;
                  this.pictureBox2.TabStop = false;
                  this.pictureBox2.MouseMove += new System.Windows.Forms.MouseEventHandler(this.pictureBox2_MouseMove);
                  this.pictureBox2.MouseDown += new System.Windows.Forms.MouseEventHandler(this.pictureBox2_MouseDown);
                  //
                  // Form1
                  //
                  this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
                  this.ClientSize = new System.Drawing.Size(504, 334);
                  this.Controls.Add(this.pictureBox2);
                  this.Controls.Add(this.pictureBox1);
                  this.Name = "Form1";
                  this.Text = "Form1";
                  this.ResumeLayout(false);

            }
            #endregion

            /// <summary>
            /// The main entry point for the application.
            /// </summary>
            [STAThread]
            static void Main()
            {
                  Application.Run(new Form1());
            }

            private void pictureBox2_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
            {
                  if (e.Button == MouseButtons.Left)
                  {
                        pictureBox2.Location = new Point(pictureBox2.Left + e.X - startX, pictureBox2.Top + e.Y - startY);
                  }

            }

            private void pictureBox2_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
            {
                  if (e.Button == MouseButtons.Left)
                  {
                        startX = e.X;
                        startY = e.Y;
                  }

            }
      }
}